North Carolina North Carolina Tar-Pamlico River Basin Tar-Pamlico River Basin

PlanPlan

Final Scoping MeetingsJanuary 30 and 31, 2001

North CarolinaNorth CarolinaCooperating Technical Cooperating Technical State Flood Mapping State Flood Mapping Program OverviewProgram Overview

Purposes of the NFIPPurposes of the NFIP

1. Make flood insuranceavailable

2. Identify floodplainareas and flood risk zones

3. Provide framework for a community’s floodplain management ordinances

With up-to-date flood hazard data:

Map users can make prudent siting, design, and flood insurance purchase decisions

Communities can administer sound floodplain management programs

Importance of Updated Importance of Updated Flood Hazard InformationFlood Hazard Information

North Carolina’s North Carolina’s Flood Mapping Flood Mapping

ProgramProgram Program established to implement the

Cooperating Technical State (CTS) Partnership with FEMA, signed September 15, 2000

Ownership and responsibility for Flood Insurance Rate Maps (FIRMs) delegatedto State

Organization of the Organization of the CTS Flood Mapping CTS Flood Mapping

ProgramProgram

NC Center for Geographic Information

and Analysis

NCGeodetic Survey

NC Division of Emergency

Management

Federal Emergency Management Agency

OSBPM

John Dorman,Program Director/Chair

CTSCommittee

Abdul Rahmani,

Project Manager

State Floodplain Mapping

ContractorGreenhorne & O’Mara, Inc.

State Floodplain Mapping

ContractorWatershed

Concepts, Inc.

Rodger Durham,

Program Manager

Mapping Coordination Contractor

Dewberry & Davis LLC

Why North Carolina Is Why North Carolina Is Undertaking This Undertaking This

ProjectProject State’s vulnerability to hurricanes

and flooding 14 federally declared disasters since 1989 Hurricane Floyd damages = $3.5 billion 4,117 uninsured/under-insured homes

destroyed as result of Hurricane Floyd Accurate, up-to-date flood hazard

information crucial to protect livesand property

Why North Carolina Is Why North Carolina Is Undertaking This Undertaking This

ProjectProject Hurricane Floyd revealed flood hazard data

and map limitations Age of North Carolina FIRMS

55% at least 10 years old 75% at least 5 years old

FEMA’s mapping budget is finite North Carolina receives only one updated

flood study for one county per year Many counties and communities lack

resources to take on this responsibility

Benefits of North Benefits of North Carolina’s CTS Carolina’s CTS

ProgramProgram Current, accurate data for sound

siting and design decisions Better floodplain management to

reduce long-term flood losses Updated data to alert at-risk

property owners of the need for flood insurance

Faster, less expensive FIRM updates

Program Program ComponentsComponents

Developing flood hazard studies through community mapping needs analysis (Scoping)

Acquiring high-resolution topographic data and accurate Digital Elevation Models (DEMs)

Conducting engineering studies Generating countywide digital FIRMs (DFIRMs) Designing and implementing state-of-the-art,

dynamic IT infrastructure Supporting real-time flood forecasting and

inundation mapping capability

Digital FIRMsDigital FIRMs

Digital FIRM=

Flood DataBase + Topography +

Digital FIRMsDigital FIRMs

Digital FIRMs will be produced in a countywide format

Will depict all flood hazard data FIRM panels will be consistent with

USGS DOQ tiling scheme

Community Review and Community Review and Due ProcessDue Process

Preliminary FIRMs provided when Tar-Pamlico River Basin Study is complete

90-day appeal period Preliminary Countywide FIRMs

provided when adjacent basin studies are complete

All appeals evaluated and resolved Final Effective FIRMs provided and

made available by the State on its Information Management System

Additional Benefits Additional Benefits of the CTS Programof the CTS Program

Digital format to allow: More efficient, precise flood risk

determinations Geographic Information System (GIS)

analysis and planning Online access 24 hours a day

DEMs will be useful for almost any engineering or planning application

Tar-Pamlico River Tar-Pamlico River BasinBasin

Extends from its headwaters in the north central Piedmont section of North Carolina to the Atlantic Ocean

Most of the upstream portion (Tar River) is freshwater, whereas the downstream portion (the Pamlico River) is entirely estuarine

Comprised of portions of 19 counties and 53 municipalities

Scoping Phase for Scoping Phase for Tar-Pamlico River Tar-Pamlico River

BasinBasinThe Scoping Phase determines: What areas are floodprone and need

flood hazard data developed Determine appropriate technical

method for developing up-to-date flood hazard data and establish priority level

How flood hazard data will be presented on FIRMs

State

State

FEMA

FEMA

KickoffMeeting with County/Local

Floodplain Administrators

MappingNeeds

Assessment

EffectiveFIS & FIRM Research

EvaluatePost-Floyd

Data

NCScoping

Database

Generate Initial

Scoping Package

InitialScoping Meetings

Develop Draft Basin Plans

Final Scoping Meetings

Finalize BasinPlans

Process for Scoping Six River Basinsin Eastern North Carolina

Prepare Delivery Orders& CTC

Mapping Activity

Agreements & Update

CTS Mapping

Agreement

Analysis and

Mapping

Step 1

Initial Research and Community

Coordination

Step 2

Initial Scoping Meeting

Step 3

Draft Basin Plans

Step 4

Final Scoping Meeting

Step 5

Final Basin Plans

SCOPING PRODUCTION

Questionnaire

Step 4 — Final Scoping Step 4 — Final Scoping MeetingMeeting

THIS IS WHERE WE ARE TODAY! All impacted counties and

communities invited Two separate Final Scoping Meetings:

January 30th - Greenville, NC January 31st - Tarboro, NC

Draft Tar-Pamlico River Basin plan presented

Provides final opportunity for input

Step 5 — Final Basin PlanStep 5 — Final Basin Plan

Draft Basin Plan may be revised following the Final Scoping Meetings

Watershed Concepts, the State’s Floodplain Mapping Contractor for the Tar-Pamlico River Basin, will develop proposals for the State

Tar-Pamlico River Basin Plan will be finalized and distributed to impacted counties and communities

Production phase will then begin

North Carolina North Carolina Tar-Pamlico River Basin Tar-Pamlico River Basin

MeetingMeeting

QQUESTIONS ON THE UESTIONS ON THE SCOPING PHASESCOPING PHASE

? ? ?? ? ?

Draft Tar-Pamlico Draft Tar-Pamlico River Basin PlanRiver Basin Plan

Summarizes scoping phase Outlines how base maps and

topography will be acquired Proposes engineering methods by

which each flooding source reach will be studied

Describes the process and schedule for completing the map production

Detailed Study — Detailed Study — RiverineRiverine

This method requires the following: DEMs Field surveys

Channel bathymetry Bridge/culvert opening geometry Channel and floodplain characteristics

Detailed Hydrologic and Hydraulic Analyses 10%, 2%, 1%, and 0.2% annual chance flood

elevations and boundaries identified (Zone AE) Floodways delineated

Riverine Areas to be Riverine Areas to be Studied in DetailStudied in Detail

(cont’d)

Riverine Areas to be Riverine Areas to be Studied in DetailStudied in Detail

(cont’d)

Riverine Areas to be Riverine Areas to be Studied in DetailStudied in Detail

(cont’d)

Riverine Areas to be Riverine Areas to be Studied in DetailStudied in Detail

(cont’d)

Riverine Areas to be Riverine Areas to be Studied in DetailStudied in Detail

RedelineationRedelineation

This method requires the following: DEMs Effective FIS flood elevations

Proposed for all areas currently shown on effective FIRM as Zone AE or VE and not being restudied

Approximate StudyApproximate Study

This method requires the following: DEMs Delineation of 1% annual chance

floodplain boundaries using approximate methods

Does not include collection/use of field-collected topographic data or bridge/culvert data

Proposed for all areas currently shown on effective FIRM as Zone A and not being restudied in detail.

Use of Effective Use of Effective InformationInformation

This method involves no new analyses or floodplain mapping

Effective FIS and FIRM data are digitized and fitted to updated base map

This method is not anticipated to be used for any communities in the Tar-Pamlico River Basin

Schedule for FIRM Schedule for FIRM ProductionProduction

(cont’d)

Schedule for FIRM Schedule for FIRM ProductionProduction

Community Review and Community Review and Due ProcessDue Process

Preliminary FIRMs provided when Tar-Pamlico River Basin Study is complete

90-day appeal period Preliminary Countywide FIRMs

provided when adjacent basin studies are complete

All appeals evaluated and resolved Final Effective FIRMs provided and

made available by the State on its Information Management System

North Carolina North Carolina Tar-Pamlico River Basin Tar-Pamlico River Basin

MeetingMeeting

QQUESTIONS ON THE UESTIONS ON THE

DRAFT BASIN PLANDRAFT BASIN PLAN

? ? ?? ? ?